Touch sensing device

ABSTRACT

In an embodiment, various active pens may be searched for in every frame, so that various active pens may operate in a touch sensing system.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority from Republic of Korea PatentApplication No. 10-2019-0173741, filed on Dec. 24, 2019, which is herebyincorporated by reference in its entirety.

BACKGROUND 1. Field of Technology

The present disclosure relates to a technology for sensing a touch or aproximity of an active pen to a touch panel and a display devicetherefor.

2. Description of the Prior Art

A technology for perceiving a touch or the proximity of an externalobject to a touch panel is called a touch sensing technology. In anelectronic apparatus using such a technology, a touch panel ispositioned in the same plane as that of a display panel, andaccordingly, a user may input user operation signals into a touch panelwhile the user looks at images on a display panel. Such a method ofgenerating user operation signals is remarkably intuitive for userscompared with previous other user operation signal input types, such asa mouse input type or a keyboard input type.

For such advantages, the touch sensing technology is applied to variouselectronic apparatuses comprising display panels. A touch sensing devicemay sense a touch or the proximity of an external object to a touchpanel by supplying a driving signal to a driving electrode disposed inthe touch panel and receiving a response signal formed in a sensingelectrode disposed therein. Here, a capacitance is formed between thedriving electrode and the sensing electrode and the change of thecapacitance may indicate a touch or the proximity of the external objectto the touch panel.

A user may use a finger as well as an active pen in order to input auser operation signal. A process of data communication between an activepen and a touch sensing device may be as follows. When a touch sensingdevice transmits an uplink signal that may be perceived by an activepen, the active pen receives the uplink signal so as to perceive thetouch sensing device. Then, when the active pen transmits a downlinksignal that may be perceived by the touch sensing device, the touchsensing device may receive the downlink signal so as to perceive theactive pen.

However, such a process is restricted to a case when a touch sensingdevice operates with one kind of active pen. When there are variousactive pens, this process cannot be applied as it is. In other words, ina case when a touch sensing device operates with various active pens,the process, of transmission and reception of an uplink signal and adownlink signal, needs to be changed. Therefore, the present disclosurewill describe a technology in which a touch sensing device operates withvarious active pens.

SUMMARY

In an aspect, the present disclosure is to provide a method of a touchsensing device's searching one of various active pens in each frame.

In another aspect, the present disclosure is to provide a method of atouch sensing device's receiving a downlink signal from one of variousactive pens in each frame.

To this end, in an aspect, the present disclosure provides a touchsensing device, for sensing a touch or the proximity of one of variousactive pens, comprising: a driving circuit to transmit an uplink signalto one of various active pens through a touch electrode; and a sensingcircuit to wait to receive a downlink signal corresponding to the uplinksignal through the touch electrode in order to search one of variousactive pens, wherein the sensing circuit searches one of the variousactive pen or all the various active pens in each frame.

In the touch sensing device, in a case when searching all the variousactive pens in each frame, the sensing circuit may sequentially searchthe various active pens.

In the touch sensing device, the sensing circuit may search a firstgroup of various active pens in a first frame and then a second group ofvarious active pens different from the first group in a second frame.

In the touch sensing device, the sensing circuit may sequentially searchthe first group of various active pens in the first frame and maysequentially search the second group of various active pens in thesecond frame.

In the touch sensing device, when the driving circuit transmits anuplink signal for one active pen in a frame, the sensing circuit maywait to receive a downlink signal corresponding to the uplink signalfrom the one active pen in each frame.

In the touch sensing device, when the driving circuit transmits uplinksignals for all the various active pens in a frame, the sensing circuitmay wait to receive downlink signals respectively corresponding to theuplink signals from all the various active pens in each frame.

In the touch sensing device, an uplink signal may comprise uplinkinformation exclusively for a kind of active pens and the sensingcircuit may search an active pen that receives the uplink information.

In the touch sensing device, uplink information exclusively for eachkind of active pens may be determined according to a data communicationprotocol for each kind of active pens.

In the touch sensing device, the sensing circuit may receive a downlinksignal from the active pen that receives the uplink information.

In the touch sensing device, the sensing circuit may receive asynchronization signal indicating display time sections and touch timesections and search one active pen or all the various active pens ineach frame in some touch time sections.

In the touch sensing device, the driving circuit may transmit uplinksignals in another touch time sections.

In the touch sensing device, downlink information exclusively for eachkind of active pens may be determined according to a data communicationprotocol for each kind of active pens.

In another aspect, the present disclosure provides a touch sensingdevice comprising: a driving circuit to transmit a first uplink signalcorresponding to a first protocol through a touch electrode in a firsttouch time section and to transmit a second uplink signal correspondingto a second protocol through the touch electrode in a second touch timesection in one frame comprising a plurality of display time sections anda plurality of touch time sections; and a sensing circuit to wait toreceive a first downlink signal corresponding to the first uplink signalin a third touch time section according to a downlink signal timingdefined by the first protocol and to wait to receive a second downlinksignal corresponding to the second uplink signal in a fourth touch timesection according to a downlink signal timing defined by the secondprotocol.

The one frame may comprise 16 touch time sections. According to thefirst protocol, downlink signals may be transmitted and received in N (Nis a natural number which is 2 or higher) of the 16 touch time sections,and according to the second protocol, downlink signals may betransmitted and received in M (M is a natural number which is 2 orhigher) of the 16 touch time sections. The third touch time section maybe selected among the N touch time sections and the fourth touch timesection may be selected among the M touch time sections to not overlapwith the third touch time section.

The driving circuit may transmit the first uplink signal in the sametouch time section in the respective frames and the second uplink signalin the same touch time section in the respective frames.

When the sensing circuit receives the first downlink signal in the thirdtouch time section, the driving circuit and the sensing circuit mayoperate according to the first protocol in the subsequent frames.

The downlink signal timing according to the first protocol may bedifferent from the downlink signal timing according to the secondprotocol.

In another frame, the driving circuit may transmit a third uplink signalcorresponding to a third protocol in one touch time section and a fourthuplink signal corresponding to a fourth protocol in another touch timesection, and the sensing circuit may wait to receive a third downlinksignal corresponding to the third uplink signal according to a downlinksignal timing defined by the third protocol and to receive a fourthdownlink signal corresponding to the fourth uplink signal according to adownlink signal timing defined by the fourth protocol.

The first uplink signal and the second uplink signal may have differentdata formats and/or communication frequencies.

Each frame may comprise 16 touch time sections and the sensing circuitmay sense a touch or the proximity of an external object to a panel insome of the 16 touch time sections.

In still another aspect, the present disclosure provides a touch sensingdevice comprising: a driving circuit to transmit a first uplink signalaccording to a first protocol in a first frame and to transmit a seconduplink signal according to a second protocol different from the firstprotocol in a second frame subsequent to the first frame; and a sensingcircuit to wait to receive a first downlink signal corresponding to thefirst uplink signal according to a downlink signal timing defined by thefirst protocol in the first frame and to wait to receive a seconddownlink signal corresponding to the second uplink signal according to adownlink signal timing defined by the second protocol in the secondframe.

The driving circuit may transmit the first uplink signal in two or moretouch time sections in the first frame and the second uplink signal intwo or more touch time sections in the second frame.

When the sensing circuit receives the first downlink signal in the firstframe, the driving circuit and the sensing circuit may operate accordingto the first protocol in the second frame.

The driving circuit may repeat the alternate transmission of the firstuplink signal and the second uplink signal in every predetermined frameperiod.

The driving circuit may transmit a third uplink signal according to athird protocol different from the first protocol the second protocol ina third frame subsequent to the second frame and the sensing circuit maywait to receive a third downlink signal corresponding to the thirduplink signal according to a downlink signal timing defined by the thirdprotocol in the third frame.

The first uplink signal and the second uplink signal may have differentdata formats and/or communication frequencies and/or downlink signaltimings.

Each frame may comprise 16 touch time sections and the sensing circuitmay sense a touch or the proximity of an external object to a panel insome of the 16 touch time sections.

As described above, the present disclosure allows various active pens tooperate in a touch sensing system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a configuration diagram of a display device according to anembodiment;

FIG. 2 is a configuration diagram of a touch sensing device according toan embodiment;

FIG. 3 is a diagram for illustrating the transmission and the receptionbetween an active pen and a panel according to an embodiment;

FIG. 4 is a diagram for illustrating the transmission and the receptionbetween one of various active pens and a panel according to anembodiment;

FIG. 5 is a diagram for illustrating uplink information exclusively forone kind of active pen in an uplink signal according to an embodiment;

FIG. 6 is a diagram for illustrating a first method of searching forvarious active pens using uplink signals according to an embodiment;

FIG. 7 is a diagram for illustrating a second method of searching forvarious active pens using uplink signals according to an embodiment;

FIG. 8 is a diagram for illustrating a third method of searching forvarious active pens using uplink signals according to an embodiment;

FIG. 9 is a first example for illustrating downlink informationexclusively for one kind of active pen in a downlink signal according toan embodiment;

FIG. 10 is a second example for illustrating downlink informationexclusively for one kind of active pen in a downlink signal according toan embodiment; and

FIG. 11 is a diagram for illustrating a second method of searchingvarious active pens using uplink signals and downlink signals accordingto an embodiment.

DETAILED DESCRIPTION

FIG. 1 is a configuration diagram of a display device according to anembodiment.

Referring to FIG. 1, a display device 100 may comprise a panel 110, adata driving device 120, a gate driving device 130, a touch sensingdevice 140, a data processing device 150, and a host 160.

A driving device comprising at least one of the data driving device 120,the gate driving device 130, the touch sensing device 140, and the dataprocessing device 150 may be referred to as a display driving device.For example, the data driving device 120 may be referred to as a displaydriving device or a driving device comprising the data driving device120 and the touch sensing device 140 may be referred to as a displaydriving device. A driving device may be included in another drivingdevice. For example, the data driving device 120 may be included in thetouch sensing device 140. Or, the gate driving device 130 may beincluded in the data driving device 120. Depending on embodiments, somecomponents of a driving device may be included in another device.

The data driving device 120 may drive a data line DL connected with apixel P and the gate driving device 130 may drive a gate line GLconnected with a pixel P. The touch sensing device 140 may drive a touchelectrode TE disposed in the panel 110.

The data driving device 120 may supply a data voltage through a dataline DL in order to display an image in each pixel P. The data drivingdevice 120 may comprise at least one data driver integrated circuit, andthis at least one data driver integrated circuit may be connected to abonding pad of the display panel 150 in a tape automated bonding (TAB)type or a chip-on-glass (COG) type, directly formed on the display panel150, or integrated on the display panel 150 depending on cases. Inaddition, the data driving device 170 may be formed in a chip-on-film(COF) type.

The data driving device 120 may receive image data and a data controlsignal DCS from the data processing device 150. The data driving device120 may generate a data voltage according to a greyscale value for eachpixel indicated by image data and drive each pixel.

The data control signal DCS may include at least one synchronizationsignal. For example, the data control signal DCS may include a verticalsynchronization signal VSYNC, a horizontal synchronization signal HSYNC,a time division signal, and the like. The data driving device 120 mayseparate a frame according to a vertical synchronization signal VSYNC,and may drive each pixel in periods other than a vertical blank periodindicated by the vertical synchronization signal VSYNC. The data drivingdevice 120 may identify image data for each horizontal line according tothe horizontal synchronization signal HSYNC, and may supply a datavoltage to each horizontal line. The data driving device 120 mayseparate a display period and a touch period according to the timedivision signal, and may drive each pixel in the display period.

The gate driving device 130 may supply scan signals to the gate lines GLin order to turn on and off a transistor located in each pixel P. Thegate driving device 130 may be positioned at only one side of the panel110 as shown in FIG. 1, or two split gate driving devices may bepositioned at both sides of the panel 110, according to a drivingmethod. In addition, the gate driving device 130 may include at leastone gate driver integrated circuit, and the at least one gate driverintegrated circuit may be connected to a bonding pad of the panel 110 bya tape-automated bonding (TAB) type or a chip-on-glass (COG) type, ormay be implemented as a GIP (gate-in-panel) type so as to be formeddirectly on the panel 110. In some cases, the gate driver integratedcircuit may be integrated to be formed on the panel 110. In addition,the gate driving device 130 may be implemented as a chip-on-film (COF)type.

The gate driving device 130 may receive a gate control signal GCS fromthe data processing device 150. The gate control signal GCS may includea plurality of clock signals. In addition, the gate driving device 130may generate scan signals using the clock signals, and may supply thescan signals to the gate lines GL.

The panel 110 may include a display panel, and may further include atouch panel (e.g., a touch screen panel (TSP)). Here, the display paneland the touch panel may share some elements with each other. Forexample, a touch electrode TE for sensing a touch on the touch panel maybe used as a common electrode to which a common voltage is supplied inthe display panel (in the case where the display panel is an LCD (liquidcrystal display) panel). As another example, the touch electrode TE maybe used as a cathode electrode to which a base voltage VSS is suppliedin the display panel (in the case where the display panel is an OLED(organic light-emitting diode) panel). Such a panel 110 may be called“integrated panel”, considering that some elements of the display paneland the touch panel are shared with each other, but the presentdisclosure is not limited thereto. In addition, an in-cell type panel inwhich the display panel and the touch panel are integrally combined isknown, but this is only an example of the above-described panel 110, andthe panel to which the present disclosure is applied is not limited tothe in-cell type panel.

Meanwhile, a plurality of touch electrodes TE may be arranged on thepanel 110, and the touch sensing device 140 may drive the touchelectrodes TE using touch driving signals. In addition, the touchsensing device 140 may generate a sensing value for a touch electrode TEaccording to a response signal generated in the touch electrode TE inresponse to the driving signal. In addition, the touch sensing device140 may calculate the touch coordinates of an object 20 using sensingvalues of a plurality of touch electrodes TE arranged in the panel 110,and the calculated touch coordinates may be transmitted to other devices(e.g., a host), and may be used therein.

The touch sensing device 140 may transmit and receive signals to andfrom the active pen 10 through the touch electrode TE. The touch sensingdevice 140 may supply an uplink signal to the touch electrode TE, andthe active pen 10 may receive the uplink signal through the contact withthe touch electrode TE. The uplink signal may include, for example,information such as panel information, protocol version, and the like, asynchronization signal, and the like. The active pen 10 may receive theuplink signal, and may identify information on the panel or the versionof the protocol, and may perform synchronization of signals.

The active pen 10 may transmit a downlink signal to the touch electrodeTE. In addition, the touch sensing device 140 may receive a downlinksignal through the touch electrode TE. The downlink signal may includestate information on the active pen. The state information on the activepen may include, for example, the position of the active pen, the buttonstate of the active pen, the battery state of the active pen, the tiltof the active pen, and the like.

The touch sensing device 140 may receive a touch control signal TCS fromthe data processing device 150. The touch control signal TCS may includeat least one synchronization signal. For example, the touch controlsignal TCS may include a vertical synchronization signal VSYNC, a timedivision signal, a touch synchronization signal TSYNC, and the like. Thetouch sensing device 140 may separate a display period and a touchperiod according to the time division signal or the touchsynchronization signal TSYNC, and may drive the touch electrode TE inthe touch period.

The synchronization signals may be of the same signal, or may be ofdifferent signals according to an embodiment. For example, the timedivision signal may be the same as the touch synchronization signal, ormay be different from the same. Hereinafter, a description may be madeusing specific names in order to emphasize specific functions thereof,but the description is not limited to the specific names.

The synchronization signals may be generated on the basis of panelcontrol signals PCS that is originally supplied from the host 160 to thedata processing device 150.

The host 160 may transmit image data to the data processing device 150,and may transmit a vertical synchronization signal VSYNC for separatingimage data by frames. The data processing device 150 may generate a timedivision signal, a touch synchronization signal TSYNC, and the like onthe basis of the vertical synchronization signal VSYNC, and may transmitthe same to each of the driving devices 120, 130, and 140.

FIG. 2 is a diagram illustrating the configuration of a touch sensingdevice according to an embodiment.

Referring to FIG. 2, a touch sensing device 140 may include a drivingunit 210 and a sensing unit 220 in one embodiment.

The driving unit 210 may supply an uplink transmission signal UTX to thetouch electrode TE in a first time period. Here, the uplink transmissionsignal UTX is an uplink signal generated in the touch electrode TE. Theuplink signal generated in the active pen may be referred to as an“uplink reception signal”.

The sensing unit 220 may receive a downlink reception signal DRX fromthe touch electrode TE in a second time period, which does not overlapthe first time period. Here, the downlink reception signal DRX is adownlink signal generated in the touch electrode TE. The downlink signalgenerated in the active pen may be referred to as a “downlinktransmission signal.”

The touch electrode TE may be a common electrode to which a commonvoltage is supplied in an LCD panel. Alternatively, the touch electrodeTE may be a cathode electrode in an OLED panel.

FIG. 3 is a diagram illustrated in order to describe an operation inwhich an active pen 10 and a panel 110 exchange link signals with eachother.

Referring to FIG. 3, a process of transmitting and receiving linksignals between an active pen 10 and a panel 110 is illustrated.

The driving unit of the touch sensing device may transmit uplink signalsUL to the active pen 10 through touch electrodes. If the active pen 10touches the panel 110 including touch electrodes or approaches the samewithin a certain distance, the active pen 10 may receive an uplinksignal UL. The uplink signal UL may be transmitted to the active pen 10through a portion or the entirety of the panel 110.

The sensing unit of the touch sensing device may receive a downlinksignal DL from the active pen 10 through the touch electrode. Uponreceiving an uplink signal UL, the active pen 10 may transmit a downlinksignal DL. The downlink signal DL may be transmitted to the touchelectrode positioned at the point that the active pen touches orapproaches.

If the downlink signal DL is supplied to the touch sensing device, thetouch sensing device may continuously transmit and receive data to andfrom the active pen 10. If the downlink signal DL is no longer suppliedto the touch sensing device at a certain time, the touch sensing devicemay search for the active pen again. That is, the touch sensing devicemay repeat the above process by retransmitting uplink signals UL to theactive pen.

FIG. 4 is a diagram illustrated in order to describe an operation inwhich various active pens and a panel exchange link signals according toan embodiment.

Referring to FIG. 4, a process of transmitting and receiving linksignals between various active pens 10-1, 10-2, 10-3 and a panel 110according to an embodiment is illustrated. Hereinafter, although threeactive pens 10-1, 10-2, and 10-3 will be described as touching orapproaching the panel 110 by way of example, the present disclosure isnot limited thereto.

The driving unit of the touch sensing device may transmit uplink signalsto various active pens 10-1, 10-2, 10-3. The driving unit mayindependently transmit uplink signals for various active pens atdifferent times. For example, the driving unit may transmit a firstuplink signal UL1 to a first active pen 10-1, a second uplink signal UL2to a second active pen 10-2, and a third uplink signal UL3 to a thirdactive pen 10-3, respectively. Here, the driving unit may transmit thefirst uplink signal UL1 to the first active pen 10-1 at a first timing,and may transmit the second uplink signal UL2 to the second active pen10-2 at a second timing, which is different from the first timing. Thedriving unit may not transmit the first uplink signal UL1 and the seconduplink signal UL2 at the same timing.

The sensing unit of the touch sensing device may wait to receivedownlink signals corresponding to the uplink signals through the touchelectrodes, thereby searching for various active pens. If a downlinksignal is received for the first time during the searching for variousactive pens, the sensing unit may continuously receive downlink signalssubsequent thereto from the active pen that transmitted the firstdownlink signal.

The sensing unit may independently search for various active pens atdifferent times. For example, the sensing unit may wait to receive afirst downlink signal DL1 from the first active pen 10-1, may wait toreceive a second downlink signal DL2 from the second active pen 10-2,and may wait to receive a third downlink signal DL3 from the thirdactive pen 10-3, respectively. Here, the sensing unit may wait toreceive the first downlink signal DL1 at a first timing, and may wait toreceive the second downlink signal DL2 at a second timing, which isdifferent from the first timing. The sensing unit may not search for thefirst active pen 10-1 and the second active pen 10-2 at the same timing.

In order to search for various active pens at different times, thesensing unit may search for one active pen among the various active pensin every frame, or may search for all of the various active pens inevery frame. The sensing unit may use one of a first scheme ofintensively searching for one active pen in one frame, a second schemeof evenly searching for various active pens in one frame, and a thirdscheme of evenly searching for some active pens in one frame and evenlysearching for some other active pens in another frame (a combination ofthe first scheme and the second scheme).

If the downlink signal is supplied to the touch sensing device from oneactive pen among the various active pens, the touch sensing device maycontinuously transmit and receive data to and from the one active pen.If the downlink signal is no longer supplied to the touch sensing deviceat a certain time, the touch sensing device may search for variousactive pens again. That is, the touch sensing device may repeat theabove process by retransmitting uplink signals to the various activepens.

FIG. 5 is a diagram illustrated in order to describe unique uplinkinformation of an uplink signal according to an embodiment.

Referring to FIG. 5, the uplink signals transmitted from the touchsensing device to various active pens may include unique uplinkinformation. The uplink information may determine a transmission andreception method such as a format, a frequency, or a timing of an uplinksignal, and, typically, may include a protocol. The uplink informationmay differ depending on the various active pens, and may includedifferent protocols depending on the various active pens. The uplinkinformation may be differently configured by the manufacturer of theactive pen.

For example, a first uplink signal for a first active pen may includefirst uplink information 510. The first uplink information 510 may be aprotocol of the first uplink signal. The first uplink information 510may include three preambles PR0 to PR2, one space, and ten symbols SB0to SB9. Each preamble may include a logic level indicating informationon the start and the end of the first uplink signal. Each symbolincludes three bits, and the whole symbols may include a total of 30bits BIT0 to BIT29. In addition, the first uplink information 510 mayhave a total signal duration of 434 μs, and may have a preamble signalduration and a symbol signal duration of 31 μs. In addition, the firstuplink signal may be transmitted at a frequency of 500 kHz through thefirst uplink information 510.

In addition, a second uplink signal for a second active pen may includesecond uplink information 520. The second uplink information 520 may bea protocol of the second uplink signal. The second uplink information520 may include two preambles PR0 to PR1, three data periods DAT1 toDAT3, and one cyclic redundancy check (CRC) period. Each preamble mayinclude a logic level indicating information on the start and the end ofthe second uplink signal. In addition, the second uplink information 520may have a total signal duration of 240 μs, and may have a preamblesignal duration, a data period signal duration, and a CRC period signalduration of 40 μs. In addition, the second uplink signal may betransmitted at a frequency of 500 kHz through the second uplinkinformation 520.

Various active pens may recognize only the uplink signal having uniqueuplink information. In order to search for a target active pen, thetouch sensing device may be required to transmit an uplink signal havingunique uplink information, which is able to be recognized by the targetactive pen, to the target active pen.

FIG. 6 is a diagram illustrated in order to describe a first scheme ofsearching for various active pens using an uplink signal according to anembodiment.

Referring to FIG. 6, a touch sensing device according to an embodimentmay search for various active pens by a first scheme indicating serialsearching or sequential searching.

The sensing unit of the touch sensing device may search for only oneactive pen among various active pens in every frame. The synchronizationsignal SYNC may determine a touch period for sensing a touch. The touchsensing device may receive a synchronization signal SYNC, and mayoperate in the touch period according to the synchronization signalSYNC. FIG. 6 illustrates only touch periods, omitting display periods,and the operation in each touch period, wherein each operation isillustrated as a waveform in the corresponding touch period.

For example, the sensing unit may search for only a first active penamong first to third active pens in a first frame FRAME1. Aftertransmitting a first uplink signal UL1, the sensing unit may search forthe first active pen in two subsequent touch periods (SS1). The sensingunit may wait to receive a downlink signal from the first active pen.The sensing unit may repeat the transmission of the first uplink signalUL1 and the searching for the first active pen (SS1) according to theduration of the first frame FRAME1.

Subsequently, the sensing unit may search for only a second active penamong the first to third active pens in a second frame FRAME2. Aftertransmitting a second uplink signal UL2, the sensing unit may search forthe second active pen in two subsequent touch periods (SS2). The sensingunit may wait to receive a downlink signal from the second active pen.The sensing unit may repeat the transmission of the second uplink signalUL2 and the searching for the second active pen (SS2) according to theduration of the second frame FRAME2.

Subsequently, the sensing unit may search for only a third active penamong the first to third active pens in a third frame FRAME3. Aftertransmitting a third uplink signal UL3, the sensing unit may search forthe third active pen in two subsequent touch periods (SS3). The sensingunit may wait to receive a downlink signal from the third active pen.The sensing unit may repeat the transmission of the third uplink signalUL3 and the searching for the third active pen (SS3) according to theduration of the third frame FRAME3.

FIG. 7 is a diagram illustrated in order to describe a second scheme ofsearching for various active pens using an uplink signal according to anembodiment.

Referring to FIG. 7, a touch sensing device according to an embodimentmay search for various active pens by a second scheme indicatingparallel searching.

The sensing unit of the touch sensing device may search for all of thevarious active pens in every frame. In this case, the sensing unit maysearch for various active pens in sequence or in a predeterminedsequence in every frame.

For example, the sensing unit may search for all of first to thirdactive pens in a first frame FRAME1. After sequentially transmittingfirst to third uplink signals UL1 to UL3, the sensing unit may searchfor the first to third active pens in a plurality of subsequent touchperiods (SS1 to SS3). The sensing unit may wait to sequentially receivedownlink signals from the first to third active pens. The sensing unitmay repeat the transmission of the first to third uplink signals UL1 toUL3 and the searching for the first to third active pens (SS1 to SS3)according to the duration of the first frame FRAME1.

Subsequently, the sensing unit may search for all of the first to thirdactive pens in a second frame FRAME2. After sequentially transmittingfirst to third uplink signals UL1 to UL3, the sensing unit may searchfor the first to third active pens in a plurality of subsequent touchperiods (SS1 to SS3). The sensing unit may wait to sequentially receivedownlink signals from the first to third active pens. The sensing unitmay repeat the transmission of the first to third uplink signals UL1 toUL3 and the searching for the first to third active pens (SS1 to SS3)according to the duration of the second frame FRAME2.

Subsequently, the sensing unit may search for all of the first to thirdactive pens in a third frame FRAMES. After sequentially transmittingfirst to third uplink signals UL1 to UL3, the sensing unit may searchfor the first to third active pens in a plurality of subsequent touchperiods (SS1 to SS3). The sensing unit may wait to sequentially receivedownlink signals from the first to third active pens. The sensing unitmay repeat the transmission of the first to third uplink signals UL1 toUL3 and the searching for the first to third active pens (SS1 to SS3)according to the duration of the third frame FRAMES.

Here, the order of transmitting the first to third uplink signals UL1 toUL3 and searching for the first to third active pens (SS1 to SS3) maydiffer in a single frame or in every frame.

FIG. 8 is a diagram illustrated in order to describe a third scheme ofsearching for various active pens using an uplink signal according to anembodiment.

Referring to FIG. 8, a touch sensing device according to an embodimentmay search for various active pens by a third scheme indicating acombination of serial searching and parallel searching.

The sensing unit of the touch sensing device may search for all ofvarious active pens in every frame while searching for all of variousfirst some active pens in one frame and while searching for all ofvarious second some active pens, which are different from the variousfirst some active pens, in another frame. In this case, the sensing unitmay search for various active pens in sequence or in a predeterminedsequence in every frame while searching for various first some activepens in sequence or in a predetermined sequence in one frame and whilesearching for various second some active pens in sequence or in apredetermined sequence in another frame.

For example, the sensing unit may search for all of various first someactive pens indicating the first to third active pens in a first frameFRAME1. After sequentially transmitting first to third uplink signalsUL1 to UL3, the sensing unit may search for the first to third activepens in a plurality of subsequent touch periods (SS1 to SS3). Thesensing unit may wait to receive downlink signals from the first tothird active pens in sequence. The sensing unit may repeat thetransmission of the first to third uplink signals UL1 to UL3 and thesearching for the first to third active pens (SS1 to SS3) according tothe duration of the first frame FRAME1.

Subsequently, like in the first frame FRAME1, the sensing unit maysearch for all of the various first some active pens including the firstto third active pens in a second frame FRAME2. The repetition in thesecond frame FRAME2 may be optional, and may not be essential.

Subsequently, the sensing unit may search for all of various second someactive pens including fourth to sixth active pens in a third frameFRAME3. After sequentially transmitting fourth to sixth uplink signalsUL4 to UL6, the sensing unit may search for the fourth to sixth activepens in a plurality of subsequent touch periods (SS4 to SS6). Thesensing unit may wait to receive downlink signals from the fourth tosixth active pens in sequence. The sensing unit may repeat thetransmission of the fourth to sixth uplink signals UL4 to UL6 and thesearching for the fourth to sixth active pens (SS4 to SS6) according tothe duration of the third frame FRAME3.

Here, the order of transmitting the first to sixth uplink signals UL1 toUL6 and searching for the first to sixth active pens (SS1 to SS6) maydiffer in a single frame or in every frame.

FIG. 9 is a diagram illustrating a first example describing uniquedownlink information of a downlink signal according to an embodiment,and FIG. 10 is a diagram illustrating a second example describing uniquedownlink information of a downlink signal according to an embodiment.

Referring to FIG. 9, downlink signals transmitted from various activepens to the touch sensing device may include unique downlinkinformation. The downlink information may determine a transmission andthe reception method such as a format, a frequency, or a timing of thedownlink signal, and, typically, may include a protocol. The downlinkinformation may differ depending on various active pens, and may includedifferent protocols depending on various active pens. The downlinkinformation may be differently configured by the manufacturer of theactive pen.

Here, if the downlink information is linked to uplink information, theprotocol for data communication determined by the manufacturer maydefine both the uplink information and the downlink information. Theprotocol may determine the timing of a signal, that is, the touchperiods in which the uplink signal and the downlink signal are to betransmitted and received. In addition, the protocol may determine thefrequencies of signals, that is, the frequency of the uplink signal andthe frequency of the downlink signal, to be the same or different.

For example, a first downlink signal for a first active pen may includefirst downlink information 910. The first downlink information 910 maybe a protocol of the first downlink signal. The first downlinkinformation 910 may define the frequency of the first downlink signal tobe 87 kHz.

The first downlink information 910 may configure a first uplink signalin 1^(st) and 9^(th) touch periods, may configure a first downlinksignal in 2^(nd) to 7^(th), 10^(th), and 14^(th) touch periods, and mayconfigure a finger in 11^(th) to 13^(th), 15^(th), and 16^(th) touchperiods, among 16 touch periods (e.g., a long horizontal blank (LHB)).The synchronization signal SYNC may determine timings of the 16 touchperiods along with display periods. In the diagram, the touch period maybe indicated as T, and the display period may be indicated as D.Accordingly, the first active pen may be required to receive the firstuplink signal and transmit the first downlink signal to conform to thetouch periods defined in the first downlink information 910.

Referring to FIG. 10, another type of downlink information isillustrated.

For example, a second downlink signal for a second active pen mayinclude second downlink information 920. The second downlink information920 may be a protocol of the second downlink signal. The second downlinkinformation 920 may define the frequency of the second downlink signalto be 114 kHz.

In addition, the second downlink information 920 may define varioustypes of downlink signals. The second downlink information 920 maydefine the position of the active pen DL2_A, the tilt of the active penDL2_B, and the state of the active pen DL2_C through the downlinksignal.

The second downlink information 920 may configure a second uplink signalin a 1^(st) touch period, may configure a second downlink signal in2^(nd), 5^(th) to 8^(th), 10^(th), and 13^(th) to 16^(th) touch periods,and may configure a finger in 3^(rd), 4^(th), 9^(th), 11^(th), and12^(th) touch periods, among 16 touch periods. The synchronizationsignal SYNC may determine timings of the 16 touch periods along withdisplay periods. Accordingly, the second active pen may be required toreceive the second uplink signal and transmit the second downlink signalto conform to the touch periods defined in the second downlinkinformation 920.

As described above, the touch sensing device may receive a downlinksignal from any one of the various active pens on the basis of thedownlink information. However, the touch sensing device may also waitpreviously to receive downlink signals from the various active pens onthe basis of the downlink information.

FIG. 11 is another diagram illustrated in order to describe a secondscheme of searching for various active pens using an uplink signal and adownlink signal according to an embodiment.

Referring to FIG. 11, a touch sensing device according to an embodimentmay search for various active pens by a second scheme indicatingparallel searching while searching for various active pens in the touchperiod defined in the protocol of each of the various active pens. Thedriving unit of the touch sensing device may transmit a plurality ofuplink signals to the respective active pens at different timings (forexample, in different touch periods). The sensing unit of the touchsensing device may wait to receive a plurality of downlink signals fromthe respective active pens at different timings (for example, indifferent touch periods). Since a plurality of uplink signals and aplurality of downlink signals are also transmitted and received so asnot to overlap each other, the searching for various active pens may beperformed such that a plurality of uplink signals does not overlap.

For example, the driving unit may transmit a first uplink signal to afirst active pen during a first touch period configured in firstdownlink information. The sensing unit may receive the first downlinksignal from the first active pen during 2^(nd), 6^(th), 10^(th), and14^(th) touch periods configured in the first downlink information.

In addition, the driving unit may transmit a second uplink signal to asecond active pen during 3^(rd) and 11^(th) touch periods configured insecond downlink information. The sensing unit may receive the seconddownlink signal from the second active pen during 4^(th) 8^(th),12^(th), and 16^(th) touch periods configured in the second downlinkinformation.

Accordingly, the touch sensing device may transmit respective uplinksignals to conform to the protocols of various active pens, and may waitto receive respective downlink signals. As described above, the serialscheme (i.e., the first scheme) may have the advantage of being able tointensively search for a specific active pen, and the parallel scheme(i.e., the second scheme) has the advantage of preventing a delay ofsearching for the active pen in every frame.

What is claimed is:
 1. A touch sensing device comprising: a drivingcircuit to transmit a first uplink signal corresponding to a firstprotocol through a touch electrode in a first touch time section and totransmit a second uplink signal corresponding to a second protocolthrough the touch electrode in a second touch time section in one framecomprising a plurality of display time sections and a plurality of touchtime sections; and a sensing circuit to wait to receive a first downlinksignal corresponding to the first uplink signal in a third touch timesection according to a downlink signal timing defined by the firstprotocol, and to wait to receive a second downlink signal correspondingto the second uplink signal in a fourth touch time section according toa downlink signal timing defined by the second protocol.
 2. The touchsensing device of claim 1, wherein the one frame comprises 16 touch timesections, downlink signals are transmitted and received in N (N is anatural number which is 2 or higher) of the 16 touch time sectionsaccording to the first protocol, downlink signals are transmitted andreceived in M (M is a natural number which is 2 or higher) of the 16touch time sections according to the second protocol, the third touchtime section is selected among the N touch time sections, and the fourthtouch time section is selected among the M touch time sections to notoverlap with the third touch time section.
 3. The touch sensing deviceof claim 1, wherein the driving circuit transmits the first uplinksignal in a same touch time section in respective frames and the seconduplink signal in a same touch time section in respective frames.
 4. Thetouch sensing device of claim 1, wherein, when the sensing circuitreceives the first downlink signal in the third touch time section, thedriving circuit and the sensing circuit operate according to the firstprotocol in subsequent frames.
 5. The touch sensing device of claim 1,wherein the downlink signal timing according to the first protocol isdifferent from the downlink signal timing according to the secondprotocol.
 6. The touch sensing device of claim 1, wherein, in anotherframe, the driving circuit transmits a third uplink signal correspondingto a third protocol in one touch time section and a fourth uplink signalcorresponding to a fourth protocol in another touch time section, andthe sensing circuit waits to receive a third downlink signalcorresponding to the third uplink signal according to a downlink signaltiming defined by the third protocol and to receive a fourth downlinksignal corresponding to the fourth uplink signal according to a downlinksignal timing defined by the fourth protocol.
 7. The touch sensingdevice of claim 1, wherein the first uplink signal and the second uplinksignal have at least one of different data formats or communicationfrequencies.
 8. The touch sensing device of claim 1, wherein each framecomprises 16 touch time sections and the sensing circuit senses a touchor a proximity of an external object to a panel in some of the 16 touchtime sections.
 9. A touch sensing device comprising: a driving circuitto transmit a first uplink signal according to a first protocol in afirst frame and to transmit a second uplink signal according to a secondprotocol different from the first protocol in a second frame subsequentto the first frame; and a sensing circuit to wait to receive a firstdownlink signal corresponding to the first uplink signal according to adownlink signal timing defined by the first protocol in the first frameand to wait to receive a second downlink signal corresponding to thesecond uplink signal according to a downlink signal timing defined bythe second protocol in the second frame.
 10. The touch sensing device ofclaim 9, wherein the driving circuit transmits the first uplink signalin two or more touch time sections in the first frame and the seconduplink signal in two or more touch time sections in the second frame.11. The touch sensing device of claim 9, wherein, when the sensingcircuit receives the first downlink signal in the first frame, thedriving circuit and the sensing circuit operate according to the firstprotocol in the second frame.
 12. The touch sensing device of claim 9,wherein the driving circuit repeats alternate transmission of the firstuplink signal and the second uplink signal in every predetermined frameperiod.
 13. The touch sensing device of claim 9, wherein the drivingcircuit transmits a third uplink signal according to a third protocoldifferent from the first protocol and the second protocol in a thirdframe subsequent to the second frame and the sensing circuit waits toreceive a third downlink signal corresponding to the third uplink signalaccording to a downlink signal timing defined by the third protocol inthe third frame.
 14. The touch sensing device of claim 9, wherein thefirst uplink signal and the second uplink signal have at least one ofdifferent data formats, communication frequencies or downlink signaltimings.
 15. The touch sensing device of claim 9, wherein each framecomprises 16 touch time sections and the sensing circuit senses a touchor a proximity of an external object to a panel in some of the 16 touchtime sections.